Washington, Dec 30 : Former US President Donald Trump and former US Ambassador to the UN Nikki Haley, the two leading candidates for the Republican party's presidential nomination, are beating President Joe Biden, the Democratic incumbent who is seeking a second term, in every match-up poll. Florida Governor Ron DeSantis, the third Republican in the race, is also ahead of President Biden, by just a bit. Biden's job approval rating is at a historic low for modern American Presidents at this stage in their respective terms. He is ending 2023 at 39 per cent, according to Gallup. Barack Obama and Donald Trump were slightly higher at 43 per cent and 45 per cent, respectively, but all the others were over 50 per cent -- Bill Clinton and George W. Bush were at 51 per cent and Ronald Reagan and Jimmy Carter were at 54 per cent. At 81, Biden is already the oldest US President in history and will be 83 if he is sworn in for a second term. Biden looks vulnerable even to Democrats, some of whom have called for him to make way for someone younger. The odds seem to be stacked against Biden, a year away from the 2024 elections. But he is running and has been upset with his numbers. The day before leaving the White House for Thanksgiving in November, Biden had summoned his aides and asked them what they were doing to reverse his poll numbers, The Washington Post had reported. The President and the First Lady have been frustrated with the low numbers that have dogged most of his presidency, but which have now acquired a sense of urgency as the presidential polls get closer. They believe that the numbers don't reflect the achievements of his administration. The economy is growing stronger, unemployment is near historic lows at just over 3%, and inflation is finally getting under control. Specially worrying has been Trump's continued lead over Biden, by 2.3 percentage points in the aggregated average of polls computed by RealClearPolitics. This is a fight that Biden and his aides believe should be easy to win. Biden has delivered on the key promise of a massive spending on infrastructure, which Trump had merely promised and re-promised. Trump is also facing four legal cases, three of which could land him in jail. Yet he leads Biden and if he stays on the ballot -- there are chances he might not because of the cases and, now, being disqualified for running by states -- he is likely to face Biden in the November elections. Haley, who is riding a surge in popularity among Republican voters looking for an alternative to Trump, is also leading Biden, and by a wider margin than Trump, at 4.9 percentage points. She has made these numbers a key part of her campaign, as she seeks to close the yawning gap between her and Trump, whose massive lead over all the Republicans in the race makes him the obvious favourite. DeSantis is also beating Biden, although not by very much, 0.2 percentage points. The Biden camp and election analysts say these polls only reflect the mood now, when the electorate is not fully tuned into the 2024 elections. Over the next few months, the Biden campaign is expected to sharpen its message, especially on the contrast between the President the Republicans, and once the Republicans have a nominee, the contest will be truly underway. /IANS